iPhone owners on AT&T had a surprise waiting for them when they installed iOS 5.1 today. As noted by The Verge, the 3G label in the status bar was replaced with one for 4G. When the iPhone 4S was released, AT&T said it was pushing Apple to make this change on the iPhone 4S and it appears the company made good on this promise.
AT&T wanted this 4G icon to distinguish its HSPA+ network from the 3G EV-DO network of Verizon. Though HSPA+ is technically not a 4G technology like LTE, it is faster than Verizon's 3G network. Whether you agree with it or not, the ITU did say companies like AT&T and T-Mobile could use the 4G label when describing their networks.
Hat tip to Jon Silva for the image